In a disrespectful manner, especially when concerning religion.(adverb)
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Use "in vain" in a sentence
"The great Temple of the Sun in Cuzco contained a massive golden image of the sun, and the walls and roof were covered with plates of solid gold, which the unfortunate Atahualja in vain delivered as a ransom to the faithless Pizarro."
"As soon as the winds shifted from west to east, Nearchus weighed anchor and sailed along the coast to a desert island called Domai, where his men searched in vain for water."
"Waiting in vain for Old Bory, Hoke fought all day against an enemy who captured part of the outer line of the Drewry's Bluff defenses."